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2 years ago

In the vertical columns of the periodic table, as the atomic numbers increase:

Chemistry

2 answers:

kolezko [41]2 years ago

5 0

A.) The number of electron shells increases.

Fiesta28 [93]2 years ago

5 0

Answer: a. the number of electron shells increases.

Explanation:

The elements in the vertical columns also called as groups are arranged in order of increasing atomic numbers and contain same valence electrons.

The electrons are added to new energy shells and the nuclear charge also increases due to increase in atomic number. But the effect of addition of new shells is more dominant.

As the shells increase, the atomic size increases and the valence shell moves farther from the nucleus , thus the tendency to lose electrons increase and thus the ionization energy which is the energy required to move the valence electron, decreases.

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In atomic science, the z number refers to the number of __________ in the nucleus of an atom.

Sliva [168]

By convention, the symbol Z is assigned to the number of protons in the nucleus, or simply, the atomic number of an element. This is actually used when you want to determine the effective nuclear charge of a specific electron of an element. The equation is:

Z* = Z - S
where
Z* is the effective nuclear charge
Z is the atomic number
S is the number of electrons between the electron in question and the nucleus

There is due to a phenomenon called the shielding effect. This effect states that the farther the electron is from the nucleus, the lesser is its pull of force to the nucleus. That is the reason why the valence electrons (outermost electrons) are the ones always involved in chemicals reactions. Because they are not that strongly bonded to the nucleus of an atom.

6 0

3 years ago

Glucose (C6H12O6) can be fermented to yield ethanol (CH3CH2OH) and carbon dioxide (CO2). C6H12O6⟶2CH3CH2OH+2CO2 The molar mass o

jekas [21]

Answer:

The % yield is 74.45 %

Explanation:

Step 1: The balanced equation

C6H12O6⟶2CH3CH2OH+2CO2

Step 2: Data given

Molar mass glucose = 180.15 g/mol

Molar mass of ethanol = 46.08 g/mol

Molar mass of carbon dioxide = 44.01 g/mol

Mass of glucose = 61.5 grams

Mass of ethanol = 23.4 grams

Step 3: Calculate moles of glucose

Moles glucose = Mass glucose / Molar mass of glucose

Moles glucose = 61.5 grams / 180.15 g/mol

Moles glucose = 0.341 moles

Step 4: Calculate moles of ethanol

1 mole of glucose consumed, produces 2 moles of ethanol and 2 moles of CO2

0.341 moles of glucose, will produce 2*0.341 = 0.682 moles of ethanol

Step 5: Calculate mass of ethanol

Mass ethanol = moles ethanol * Molar mass ethanol

Mass ethanol = 0.682 moles * 46.08 g/mol

Mass ethanol = 31.43 grams = theoretical mass

Step 6: Calculate % yield

% yield = actual mass / theoretical mass

% yield = (23.4 grams / 31.43 grams) * 100%

% yield = 74.45 %

The % yield is 74.45 %

7 0

3 years ago

What volume of Co2 (carbon (iv) oxide)

hram777 [196]

Answer:

2.1056L or 2105.6mL

Explanation:

We'll begin by calculating the number of mole in 10g of Na2CO3. This can be obtained as follow:

Molar mass of Na2CO3 = (23x2) + 12 + (16x3) = 106g/mol

Mass of Na2CO3 = 10g

Mole of Na2CO3 =.?

Mole = mass /molar mass

Mole of Na2CO3 = 10/106

Mole of Na2CO3 = 0.094 mole

Next, we shall determine the number of mole CO2 produced by the reaction of 0.094 mole of Na2CO3. This is illustrated below:

Na2CO3 + 2HCl —> 2NaCl + H2O + CO2

From the balanced equation above,

1 mole of Na2CO3 reacted to produce 1 mole of CO2.

Therefore, 0.094 mole of Na2CO3 will also react to 0.094 mole of CO2.

Next, we shall determine the volume occupied by 0.094 mole of CO2 at STP. This is illustrated below:

1 mole of a gas occupy 22.4L at STP. This implies that 1 mole CO2 occupies 22.4L at STP.

Now, if 1 mole of CO2 occupy 22.4L at STP, then, 0.094 mole of CO2 will occupy = 0.094 x 22.4 = 2.1056L

Therefore, the volume of CO2 produced is 2.1056L or 2105.6mL

7 0

3 years ago

3. The scientific study of how organisms are classified is called _____.

Vilka [71]

Hey mate!

Taxonomy is the study of classification of organisms. Therefore, your answer is A.

Hope this helps!

3 0

3 years ago

Quick electron emissions are called

Montano1993 [528]

Defined as a phenomenon of liberation of electron from the surface that is stimulated by temperature elevation, radiation, or by strong electric field.

3 0

2 years ago